Correlation of Upper Triassic strata in Qiangtang Basin, northern Tibet

Abstract：There exist Upper Triassic Riganpeicuo Formation, Tumengela Formation, Xiaochaka Formation and Nadigangri Formation in Qiangtang basin, with the first two formations distributed in the southern part whereas the last two distributed in the northern part of Qiangtang depression. Based on a detailed comparative study of the oil-gas resource potential in major sedimentary basins of the Qinghai-Tibet Plateau, the authors analyzed the paleontology, lithologic assemblage, sedimentary sequence, contact relationship and chronostratigraphic features. The results show that Nadigangri Formation, Riganpeicuo Formation and Tumengela Formation occurred mainly during the formation of the rift basin in Late Triassic Norian and Rhaetian periods, whereas the Xiaochaka Formation was generated from Carnian to early Norian periods, showing comparative correlation with Nadigangri Formation, Riganpeicuo Formation and Tumengela Formation.